I needed new tires (camber ware) I had the Nitto 555. I end up getting the Felken FK 452. I asked for the same size I have now, 245/35/20 front & 275/30/20 rear. When they put the tires on the rear tires looked stretched I looked at the size & it did have 275/30/20 on them. So they put on 285/30/20 & they looked the same as the Nitto's 275's looked. Why is that? isn't 275's the same on all brand tires?

 

Because a 275 from Nitto is the same exact size as a 275 from Falken.

I bet if you went to the maker's website and looked up the phyiscal specs for each, you'd find a different width spec for both. My Michelins in the 255-35 are a touch thinner vs the oem Re050s in 245-40.

 

I noticed that too. My Michelin PS2 275/35/19's were much wider than my Toyo T1R's in the same size which is why I moved up to a 285. It struck me as odd too since I thought there was a strict standardization when it came to tire size.

 

++1000, i noticed this on a member's PS2 but it was vice-versa compared to yours^. Instead, my toyo's had a normal look while he had a more stretch-look on his PS2. Both rims were 19x10.5. Both our tire size were 285/35/19's.

Nevertheless, i think it might be the tread width specification(or contact area width). You''ll notice on tirerack under each tire's specs, that the tread widths are different with the same tire size depending on brand and model. It's my best guess

 

yup, no one tire from manufacture to manufacture is the same even though they state the same size. Nitto's are known to run wide, i've heard bridgestone michelin and pirelli all run narrow.